GEN (ONE) IN

inform one fully. Also commonly give one the gen: give one the detailed information. From military service slang, especially the British Royal Air Force, it comes from either "general information" or "genuine." —HSSC Glossary (approved 3-9-90)

inform one fully. Also commonly give one the gen give one the detailed information. From military service slang, especially the British Royal Air Force, it comes from either "general information" or "genuine."inform one fully. Also commonly give one the gen give one the detailed information. From military service slang, especially the British Royal Air Force, it comes from either "general information" or "genuine." Why do you say such things as that, except to gen him in. -Principles of Auditing (5 Sept. 61)